document.write( "Question 644445: The profit earned when an article is sold for Rs.78 is twice as much as when it is sold for Rs.69. Find the cost price of the article \n" ); document.write( "

Algebra.Com's Answer #405050 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+x+\"$ = the price of the article
\n" ); document.write( "Let $\"+p+\"$ = the profit when the article
\n" ); document.write( "is sold for Rs. 69
\n" ); document.write( "given:
\n" ); document.write( " $\"+2p+\"$ = the profit when article is
\n" ); document.write( "sold for Rs. 78
\n" ); document.write( "---------------------------
\n" ); document.write( "(1) $\"+69+-+x+=+p+\"$
\n" ); document.write( "(2) $\"+78+-+x+=+2p+\"$
\n" ); document.write( "----------------
\n" ); document.write( "Subtract (1) from (2)
\n" ); document.write( "(2) $\"+78+-+x+=+2p+\"$
\n" ); document.write( "(1) $\"+-69+%2B+x+=+-p+\"$
\n" ); document.write( " $\"+9+=+p+\"$
\n" ); document.write( "-----------------
\n" ); document.write( "Substitute this result back into (1) or (2)
\n" ); document.write( "(1) $\"+69+-+x+=+9+\"$
\n" ); document.write( "(1) $\"+x+=+69+-+9+\"$
\n" ); document.write( "(1) $\"+x+=+60+\"$
\n" ); document.write( "The cost price was Rs. 60
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+78+-+x+=+2%2A9+\"$
\n" ); document.write( "(2) $\"+x+=+78+-+18+\"$
\n" ); document.write( "(2) $\"+x+=+60+\"$
\n" ); document.write( "OK \n" ); document.write( "

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